Speak With A Forked Tongue Meaning

(idiomatic) To speak deceptively; to be duplicitous or untruthful.

Example: 2008 March 26, "Let a real "probe" begin," Sandusky Register online (retrieved 26 Mar 2008):
  He's spoken with a forked tongue to reporters, and his explanations for launching a probe don't pass the plausibility and credibility tests.